Electrical pulse regulator



llarch 1, 1949. N. H. MILDE ELECTRICAL PULSE REGULATOR Filed Oct. 29, .1946

Patented Mar. 1, 1949 UNITED: STATES PATENT OFFICE ELECTRICAL PULSE REGULATOR Norman H. Milde, Torrance, Calif.

Applicationflctobcr 29,,194'6,,Serial No. 706,496.

aClaims, (Cl. 17'7 -380) (Granted under the act of March 3, 1883, as

amended April 3'0, 1928; 370 O. G. 757) 1. Ihe invention described-herein may be manufactured by or for the Unitedstates Government for governmental purposes without payment to me of any royalty thereon.

right side and rack 2' is on theleft side of the aircraft. For each bomb carried in the racks there isv a solenoid and trip mechanism 3 on the respective racks to provide independent release The present invention relates to an electrical 5 means for each bomb. Each of the solenoid and pulse regulator, and the inventionis adapted'for trip mechanisms 3 is connected by electrical use wherever'it is desired toprovide an electrical cables to a rack selector unit 4 which is adapted signal. of predetermined) duration and intensity. to. automatically operate the bomb trip mecha- The principal object of the invention is to pronisms. ina preselected sequence. For instance, vicle an electrical timing circuit capable of proit is common practice to connect the trip mechaducing a. signal of definite and. predetermined nisms to the selector in such manner as to cause duration, regardless of the duration. of'the cir release of bombs from opposite sides of the aircuit initiating signal. craft alternately and thus keep the craft in In releasing bombs from aircraft it is currently proper trim or balance. In order to provide prepossible to initiate the'bomb release sequence or determined, and uniform time intervals between operation by several-different control deviceseach the dropping off each bomb, release signals are of which may providean electrical pulse, or imfed to the rack selector unit 4 through a bomb pulse, of differentduration and possibly of difreleaseinterval control unit or intervalometer 5 ferent electrical characteristics. However for which includes manual control means capable of proper operation of. the bomb release circuitit being set in accordance with the ground speed ishighly desirable thatia. pulse oidefinite. duraof the aircraft and. the desired spacing of bombs tion and strength he provided. Thus it isa. furto produce impulses which act on the rack" sethcr object of the invention to provide an. imlector unit 4 to. give a desired bombing pattern. proved bomb release; circuit or system including The bomb release system includesa control panel atiming circuit. or regulator intermediate of, the 6 having a pair of. switches l and T and also bomb release initiating means and. the. bomb resignal lights as at 8 to-indicate the release of'each lease devices capable-of delivering a signal of preindividual bomb. The switch I has twoseparate determineddurationinresponse to an initiating on positions providing circuits whereby the impulse of variable and unpredictable duration. hand-grip push button switch 9' is connectedfor Another object of the. invention is to provide 39 releasing the bombs one at a timev manually or a combination of magnetic and time delay relays for releasing thebombs in atrain uponactuation connected into-a common circuit and adapted to of the push button. When. the, train setting is produce an electrical impulse of definite duration used the bombs will fall in. a predetermined pat.- in response to initiating signalsv of irregular and tern according to the setting of the bomb re,- indefinite duration. lease interval control unit 5 and the connections A further object of the. invention. is to genasmadebetweenthe rack selector unit land the erally improve the construction and arrangement bomb trip mechanisms 3. The switch I, which ofbomb release circuits, and to provide an immerely has on and on positions, is for the proved electrical timing, circuit. having general purpose of simultaneously releasing all the-bombs applications as well, as aparticular application .40 ina salvo. in=controllingibomb releasev circuits. The bomb release circuit and apparatus as The above,v and other objects will become apdescribed in the preceding paragraph may be parent on reading thefollowing specification and initiated or set in motion by electrical impulses claims in conjunction with, the accompanying from various sources such as the push button drawing, in which: bomb release switch 9, by the automatic bomb Fig. 1 is aschematic wiring diagram of a comsight in or by a radio signal picked up by the plete bomb release circuit embodying the elecradio receiver'llon the aircraft. The bomb sight trical pulse regulator of the present invention. Ill includes an automatic switch adapted to close is a Wiri d ra of t electrica when a preset contact member is engaged by a pulse regulatorforming'one'unit'of-the bomb remotor driven. pick-up arm synchronized by the lease circuit shown in Fig: 'bombardier when the target is initially sighted.

Referring to Fig. 1' there is shown diagram- Closing the bomb sight automatic switch or'the matically apair of bomb racks i and 2 which bomb. release switch 9 completes a circuit from a may be" considered as installed in an aircraft on source of potential to the input terminal A- of opposite? sides" thereof, sothat rack l ison the the electrical pulse regulator l2, which terminal 3 may also be connected to the output of radio receiver I I. The radio receiver is mostly used in formation flights in which the leading aircraft is equipped to send out a radio signal for triggering the bomb release systems of the other aircraft in the formation.

In the present invention direct actuation of the interval control unit, rack selector and bomb trip mechanisms by the bomb release initiating means is avoided because these various types of initiating signals are not of uniform and predetermined duration. Instead the electrical pulse regulator I2 receives the bomb release initiating signal at input terminal A and delivers a regulated impulse at output terminal C connected to the interval control unit 5. The interval control unit which may vary in design considerably is dependent for proper operation on receiving an initiating pulse of definite and predetermined duration. For instance the interval control unit may comprise a timing circuit which includes a condenser and resistor network capable of storing a charge and then releasing the charge in spaced surges through a relay for actuation of the rack selector and bomb trip mechanisms. Alternatively this timing circuit or intervalometer may include a vacuum tube or a gas-filled tube such as a Thyratron, or the circuit may include an electro-mechanical timer set in motion by a relay-actuated motor. In any event the successful operation of the interval control unit or intervalometer depends on the input pulse being of definite duration, the length of which will be predetermined Within close limits by the design of the interval control unit which it is desired to use. While the duration of the impulse may accordingly vary considerably the range required with interval control units now commonly used is about 0.05 to 0.1 second, and the components of the pulse regulator I2 may be chosen to provide an output impulse having an exact duration which will fall somewhere within this range. Even though the present electrical pulse regulator 12 provides an output of a definite duration it is adapted to be set in operation or triggered by various bomb release initiating means such as the bomb release switch 9, the automatic bomb sight in or the radio receiver ll. While the duration of the output pulse will usually fall within the above stated time range it should be understood that the invention is in no way limited to providing an impulse of any fixed duration or range, since the time range given is merely stated by way of example.

The electrical pulse regulator I2 indicated in Fig. 1 as forming part of the bomb release system is shown in detail in Fig. 2. The principal components of the regulator are the magnetic relay RE-l, the magnetic relay RE2, the time delay relay RE--3 and the on-off switch [3. A source of potential such as the battery I4 is connected to the ground terminal B and also to the switch l3 as shown. This source of electrical potential will always determine the electrical characteristics of the output pulse of the regulator l2, and may be designed or selected accordingly with this feature in mind. The relay RE-l' may be termed the input relay and the relay RE-3 may be termed the output relay because of their relative positions and purposes, as will be seen.

The magnetic relay RE--I includes a holding coil or operating coil l5 which may be energized to move the relay contactor l6 downward against the force of a tension spring, I1 and thus break the circuit through contact l8 leading to the holding coil IQ of relay RE2. The initiating impulse to the circuit is through the terminal A, through the holding coil I5 and thence to the ground terminal B, it being understood that the ground forms one conductor from the source of the initiating impulse. The initiating impulse regardless of its duration will actuate the relay RE-l thus breaking the circuit from relay contactor Hi to the coil l9 of relay RBI-2. The impulse also energizes holding coil or operating coil 29 of relay RE2 through contact 2! and auxiliary contactor 22 of the same relay, thus moving the main relay contactors 23, 24 and 25 downwardly against the action of a tension spring 26 to close three circuits at the same time.

Energizing the relay RE-2 to move the contactors downwardly causes contactor 23 to close a circuit through the auxiliary contactor 22 to lock in the holding coil 20 by using the potential source 14. As the contactor 23 is pulled down it first contacts the auxiliary contactor 22 to close the relay lock-in circuit and then moves the contactor 22 downward against the action of the compression spring 22' far enough to break the circuit from the input terminal A to the holding coil 20. Thus it is clear that the auxiliary contactor 22 is operated only by the contactor 23 and not directly by the relay holding coils. This type of relay is usually known as a make-before-break relay, and may include various mechanical arrangements for effecting the desired result. The relay contactor 24 closes a circuit from the potential source 14 to the output terminal C by way of the contact 21, contactor 29 of time delay relay RE-3 and contact 39 of the latter relay. The other terminal of the battery l4 being grounded, the impulse circuit to the interval control unit 5 is completed by means of a ground connection made thereto. The output impulse of the circuit is thus started by closing the contactor 24 on its contact 21 and the electrical characteristics of the impulse is determined by the type of battery or potential source M which is used. The contactor 25 completes a circuit from the battery or potential source M to the coil 32 of the time delay relay RE3, the contactor 25 completing its circuit through contact 28.

The time delay relay RE3 actually governs the duration of the output pulse delivered by the relay system which forms the electrical pulse regulator. Obviously various types of relays may be used depending on the pulse duration desired. For instance the hot wire type or the bimetallic thermal strip type are relatively slow acting, while the dashpot type or the copper slug type are usually much faster. In the present embodiment the copper slug relay RE3 is illustrated and is preferred in the bomb release system of Fig. 1 for its reliability and its relative quick action. This type of relay is useful only with direct current but the system of Fig. 1 usually depends for power on storage batteries carried by the aircraft. The delayed action of this relay is due to the slow build-up of magnetic fiux in the iron core element 33 caused by the hysteresis efiect of the copper slugs or washers 34 placed between the coil 32 and the relay contactor 29. When current is turned on in the coil 32 a heavy current is momentarily induced in the copper slugs as the lines of fiux cut the slugs. This acts to delay the building up of magnetic fiux in the portion of the core 33 nearer to the contactor 29, since the slugs act to absorb the magnetic flux formed by the coil 32. This hysteresis efiect dies out as the direct current flowing reaches a steady state, and the core 33 then attracts the contactor 29 which thus-breaks thecircuit through contact 3m to terminatethe output pulse of the relay' system; The copper slugs may be of various thicknesses and'--maybe reduced in number also; A relay which-was designed for this-same circuithad' only one slughaving a thickness almost equal tothe space-taken up by thawindings-of coil 32.- I he design of the-relay will determinethe-speedwith which it acts but in general the-copper slug type oi 'relay is used for timedelays of- 0.1-. second or less. The coil and slugs structure of the relay maybe termed a timing-element; since' it determines 'th'e timedelay' characteristic of the relay When therelay RE sects to move the contactor 2-91to the: leftagainst the force oftension spring-35' the contactor engages contact 31", which is; connected to] the oontactor lfi of? relayx-RE -l Atusuc'h'. time as the. initiating: current for the relayccircuitz' is. cut off, theiholding: coil l of relay RE-e-i. is. deenergized and...therefore the contactor It; moves upwardly to close a. circuit from: the battery l lthrough-contactor 2 1 and contact; 2] of. relay RE'2 ,1 through contactor- 29 and; contact: 3i: of relay RE-i-b, and: thence through contactor: IE and contact;.l szof. the relay RE+-lztoptha coil Lot relayrRE-Z. Since the coil i9; is provided with, more. turns. than. coil iifixandisince it acts: ontherelay-RE-Qiin. azdirectionaopposite to that of. coil the'relayicontactors. 23, Hand. are, immediately'iorceduprwardly. Moving the contactor 23 upwardly breaksv the lock-in circuit .of holding coil: 20: and also allows the auxiliary; contactor- 22.v to again close the line between the holding coil 20: and the relay input terminal A. Moving the contactor 24 upwardly breaks the circuit to the coil l9 from the battery. Mg. and. moving contactor 25 upwardly breaks the circuit from the battery to the coil 32 of the time delay relay, RE-d. The springs 26 and 35 act to hold the contactors of the relays RE2 and RE-3 in the deenergized positions, as shown in Fig. 2. Thus it is seen that the relay system recyclesas soonasthe initiating pulse terminates, assuming, that the relay RE"I3"has had time t-ogb'reak the output rcuit'to output terminal C.v andimove-the. contact'or. Zsinto engagement with the contact 3.1. Recycling, which may be definedias restoration ofthe relays to their original deenergized positions, is thus complete when the time delay relay RE -3 has its contactor 29 restored to its original position of engagement with contact 30, upon breaking of the circuit to coil 32 through contactor 25 of relay RE-Z.

If the initiating pulse of the relay system is of shorter duration than the output pulse then the contactor it of the relay REI will move upwardly before the contactor 29 of relay RE3 has had time to engage the contact 3|. In this event recycling of the relays will not start until the relay RE3 has acted to break the output circuit through contact 30 and make its other or recycling circuit by engagement of the contactor 29 and the contact 3|. To summarize these operations it might be stated that the relay recycling takes place when the initiating pulse terminates if the output pulse has ceased. Conversely immediate recycling takes place at the end of the output pulse if the initiating pulse has stopped.

By means of the relay system as described above a dependable electrical pulse regulator is provided. The system includes only one variable that affects the pulse duration and that is the time delay relay which must be chosen for the pulse duration desired. The obvious advantages recommend the relay system for general uses as "well as in a bomb release system as described above. The relaysystem disclosed: is particularly unique in its ability to produce an electrical lmPlllSeOf uniform duration regardless of the length of the initiating impulse applied thereto; and'its ability toproduce onlyone such irnpulse even-though: the: initiating impulse: persists indefinitely.

The embodiments of; the invention: herein shown and describedar zto: be regarded; as illusitrative only and' itiis to: be understood that the invention is susceptible to variations, modifications and changes; Within. the scope of the appended clain'i's:

Iiclaimr 1; An electrical pulse. regulator for. connection iman; electrical bomb release. system. between. a systeminitiating means. and. a. bomb release" in-. tervalometer, said: regulator comprising; a:.mag;- netic. relay having: contactors adapted.v to. be actuated inone direction; by means: of an. input pulse of indeterminate duration, a time. delayrelay including a timing-element: and including means to connecta: constant. source of electrical potential tothe outputterminals of the. pulse regulator. when saidmagnetic: relay contactors are actuated in said one direction; means included in said" magnetic relay to complete" a circuit to the timing element of said time delay relay when said contactors areactuated in said one d-irection whereby the potential supplied to said output terminalsiscut olf'when said timing elementacts to energizexsaid time delay relay, means actuated in response to-termination of said input pulse after said time'delay relay has-beenenergized to actuate said contactors in the opposite direction and thus break theci'rcuit' tothe timingelement of 'saidtime delay relay;

2'." An electrical'pulse regulator for connection inanelectrical bomb release system between a system initiating means and a bomb release intervalometer, said-regulator comprising an input relay' adapted to be energized'by'aninput signal of indefinite duration, a second relay having contactorsadaptedto be actuated in two directions, means responsive tosaid" input signal toactuate sald contactors in one direction, a-- third relay includinga timing element to providea definite time delay before energization, said third relay including means adapted to connect a constant source of electrical potential to the output terminals of the pulse regulator when said contactors are actuated in said one direction, means included in said second relay to complete a circuit to the timing element of said third relay when said contactors are actuated in said one direction, whereby the potential supplied to said output terminals is cut off when said timing element acts to energize said third relay, means included in said third relay to complete a circuit through said input relay when said input signal terminates and after said third relay has been energized, and means included in said latter circuit to actuate said second relay contactors in the other direction to break the circuit to said timing element and thus deenergize said third relay.

3. An electrical pulse regulator comprising, a magnetic relay having a plurality of contactors adapted to be actuated in two directions. means responsive to an input signal to actuate said contactors in one direction, a time delay relay having a timing element and including means to connect a constant source of electrical potential to the output terminals of the pulse regulator through one of said contactors when said contactors are actuated in said one direction, another of said contactors being adapted to complete a circuit to said timing element when said contactors are actuated in said one direction, energization of said time delay relay by action of said timing element being adapted to break the circuit to said output terminals and to complete another circuit for recycling said relays upon termination of said input signal, and means for recycling said relays including means adapted to actuate said contactors in the other of said directions.

4. An electrical pulse regulator for connection in an electrical bomb release system between a system initiating means and a bomb release intervalometer adapted to supply a series of timespaced electrical signals to the bomb trip mechanisms of said system, said regulator comprising an input relay adapted to be energized by an input signal from said system initiating means, a time delay relay having an energizing means and being adapted to complete separate circuits through a movable contactor thereof in both the unenergized and the energized positions of the contactor, a magnetic relay responsive to said input signal for completing the unenergized circuit of said time delay relay to the output terminals of the pulse regulator through a constant potential source and the time delay relay contactor, and for energizing said time delay relay after a predetermined time delay period which determines the duration of the output pulse of the pulse regulator, a relay recycling means to I restore the relays to their original unenergized positions, energization of said time delay relay after said time delay period being operative to open the circuit to said output terminals and close a circuit through said time delay relay contactor, said input relay and said potential source to said relay recycling means after termination of said input signal, thus recycling said relays and breaking the circuits originally completed by said magnetic relay in response to said input signal.

5. An electrical pulse regulator for connection in an electrical bomb release system between a system initiating means and a bomb release intervalometer adapted to supply a series of timespaced electrical signals to the bomb trip mechanisms of said system, said regulator comprising an input relay adapted to be energized by an input signal from said system initiating means, a second relay having contactors adapted to be actuated in two directions, a first electro-magnetic means forming part of said second relay responsive to energization by said input signal to actuate said contactors in one direction, a time delay relay having an energizing means and be-- ing adapted to complete separate circuits through a movable contactor thereof in both the unenergized and the energized positions of the contactor, actuation of said second relay contactors in said one direction being operative to complete a circuit to the time delay relay energizing means, to the output terminals of the pulse regulator through a constant potential source and the time delay relay contactor, and to said first electro-magnetic means through said potential source, energization of said time delay relay after a predetermined time delay period being opera tive to open the circuit to said output terminals and close a circuit through said time delay relay contactor, said input relay and said potential source to a second electro-magnetic means forming part of said second relay after termination of said input signal, said second electro-magnetic means acting in opposition to said first electromagnetic means and being adapted to overpower said first electro-magnetic means to actuate said second relay contactors in the other direction, thus breaking the circuits originally completed by said latter contactors and recycling the relays of said pulse regulator.

NORMAN H. MILDE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,781,497 Crago Nov. 11, 1930 1,913,699 Crago June 13, 1933 1,965,377 Hicks July 3, 1934 2,029,699 Bowne Feb. 4, 1936 2,347,481 Hooven Apr. 25, 1944 2,347,777 Hanscom May 2, 1944 

